knackered
\NAK-erd\
adjective
1. British Slang. exhausted; very tired: He is really knackered after work.
Quotes
“It’s been … exhausting,” Oborne says, sounding a little dazed. “I’m all right. I’m a bit knackered. I expected it to be well covered, but I didn’t expect it to be on the front page. But I haven’t seen any schadenfreude. There’s been no glee.”
-- Archie Bland, "Peter Oborne: what I have seen is unprecedented in a quality newspaper," The Guardian, February 18, 2015
Origin
Knackered entered English in the late 1800s from the verb knacker meaning "to tire."
Dictionary.com